Method of forming a roofing product including a ceramic base material and recycled roofing material

ABSTRACT

A method of forming a roofing product can include providing a ceramic base material having an open structure, and filling the open structure of the ceramic base material with a bituminous material. In a particular embodiment, the bituminous material has no greater than approximately 5 weight % of abrasive particles or has a first particle size distribution. The method can further include applying a recycled roofing material. In an embodiment, the recycled roofing material is applied along a principal surface of the ceramic base material or adjacent to the ceramic base material. In a particular embodiment, the recycled roofing material has at least 2 weight % acid-insoluble solids or has a second particle size distribution that is narrower than the first particle size distribution.

RELATED APPLICATIONS

This is a continuation of and claims priority under 35 U.S.C. §120 toU.S. patent application Ser. No. 12/619,168 entitled “Method of Forminga Roofing Product Including a Ceramic Base Material and Recycled RoofingMaterial” by Kalkanoglu et al. filed on Nov. 16, 2009, which is relatedto and claims priority under 35 U.S.C. §119(e) to U.S. PatentApplication No. 61/118,181 entitled “Roofing Product Including a CeramicBase Material and Recycled Roofing Material and a Method of Forming theSame” by Kalkanoglu et al. filed on Nov. 26, 2008, both of which areassigned to the current assignee hereof and incorporated herein byreference in their entireties. This is related to U.S. patentapplication Ser. No. 12/619,155 entitled “Roofing Product Including aCeramic Base Material and Recycled Roofing Material” by Kalkanoglu etal. filed on Nov. 16, 2009, which is assigned to the current assigneehereof and incorporated herein by reference in its entirety.

FIELD OF THE DISCLOSURE

The present disclosure relates to roofing products and methods offorming roofing products, and more particularly to, roofing productsincluding ceramic base materials and recycled roofing material andmethods of forming the same.

RELATED ART

Roofing products can be in different forms, such as shingles ormembranes. The roofing products can include a base material and abituminous material. The base material can include wood, a woodderivative (e.g., paper), fiberglass, organic fibers (e.g., polyester),or the like. Conventionally, the bituminous material can includeasphalt, a filler, and potentially a plasticizer. A variety of fillershas been used including limestone, talc, fly ash, coal fines, or otherrelatively inert materials. Limestone has been most commonly used asfiller in roofing products due to its relatively low cost and itscompatibility with a wide variety of materials used for roofingproducts. Traditionally, recycled roofing material has not been used inroofing products.

Currently, recycled roofing materials are being considered for use informing new roofing products. Methods have been proposed to rejuvenatethe bituminous material and to remove roofing nails from the recycledroofing material. Regardless whether a roofing product includes or doesnot include recycled roofing material, the roofing product must still beable to withstand the rigors of shipping and handling, installation, andexposure to outdoor environments for several years.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments are illustrated by way of example and are not limited in theaccompanying figures.

FIG. 1 includes a process flow diagram illustrating an exemplary methodof forming a roofing product.

FIG. 2 includes an illustration of a particle size distribution ofconventional limestone filler within an asphalt coating.

FIG. 3 includes an illustration of a particle size distribution ofrecycled roofing material.

FIG. 4 includes a simplified block diagram illustrating a portion of anapparatus used in manufacturing a shingle-type roofing product.

FIG. 5 includes an illustration of a cross-sectional view of a finishedroofing product including a ceramic base material and a layer ofrecycled roofing material.

FIG. 6 includes a simplified block diagram illustrating a portion of anapparatus used in manufacturing a membrane-type roofing product.

FIG. 7 includes an illustration of a cross-sectional view of anotherfinished roofing product including a ceramic base material and a layerof recycled roofing material.

FIGS. 8 and 9 include bar graphs illustrating results of tear tests forinitially made and aged roofing products.

Skilled artisans appreciate that elements in the figures are illustratedfor simplicity and clarity and have not necessarily been drawn to scale.For example, the dimensions of some of the elements in the figures maybe exaggerated relative to other elements to help to improveunderstanding of embodiments of the invention.

DETAILED DESCRIPTION

The following description in combination with the figures is provided toassist in understanding the teachings disclosed herein. The followingdiscussion will focus on specific implementations and embodiments of theteachings. This focus is provided to assist in describing the teachingsand should not be interpreted as a limitation on the scope orapplicability of the teachings.

Before addressing details of embodiments described below, some terms aredefined or clarified. The term “abrasive particle” is intended to mean aparticle having a hardness at least as hard as a ceramic base materialused or to be used within the same roofing product.

The term “perimeter volume” is intended to mean a volume generallydefined by outer surfaces of an object. For example, a fiberglass matcan include glass fibers in the form of an open structure. The outersurfaces of the fiberglass mat are used to determine the perimetervolume. The volume occupied by only the glass fibers within thefiberglass mat may be substantially less than the perimeter volume.

The term “principal surfaces,” with respect to a roofing article orproduct, is intended to mean a pair of opposite surfaces of such roofingarticle or product, wherein one of the surfaces lies or would liefarther from a structure to which the roofing article or product isinstalled or intended to be installed, and the other surface of suchroofing article or article lies or would lie closer to a structure towhich the roofing article or article is installed or intended to beinstalled. When installed, the principal surface farther from thestructure may be directly exposed to an outdoor environment, and theother principal surface may contact the structure or a different roofingarticle or product that lies between the other principal surface and thestructure.

The term “recycled roofing material” is intended to mean a material thatincludes at least some roofing article content that is or will become alayer within a roofing product. Recycled roofing material may include atleast some material that is not recycled.

The term “roofing article” is intended to mean a roofing product(recently manufactured or used) or a byproduct of a roofingmanufacturing process that can be recycled and used to make a newlymanufactured roofing product.

The term “roofing product” is intended to mean a final product or anintermediate product of a roofing manufacturing process.

As used herein, the terms “comprises,” “comprising,” “includes,”“including,” “has,” “having” or any other variation thereof, areintended to cover a non-exclusive inclusion. For example, a method,article, or apparatus that comprises a list of features is notnecessarily limited only to those features but may include otherfeatures not expressly listed or inherent to such method, article, orapparatus. Further, unless expressly stated to the contrary, “or” refersto an inclusive-or and not to an exclusive-or. For example, a conditionA or B is satisfied by any one of the following: A is true (or present)and B is false (or not present), A is false (or not present) and B istrue (or present), and both A and B are true (or present).

Also, the use of “a” or “an” is employed to describe elements andcomponents described herein. This is done merely for convenience and togive a general sense of the scope of the invention. This descriptionshould be read to include one or at least one and the singular alsoincludes the plural, or vice versa, unless it is clear that it is meantotherwise. For example, when a single item is described herein, morethan one item may be used in place of a single item. Similarly, wheremore than one item is described herein, a single item may be substitutedfor that more than one item.

Unless otherwise defined, all technical and scientific terms used hereinhave the same meaning as commonly understood by one of ordinary skill inthe art to which this invention belongs. The materials, methods, andexamples are illustrative only and not intended to be limiting. To theextent not described herein, many details regarding specific materialsand processing acts are conventional and may be found in textbooks andother sources within the roofing product arts and correspondingmanufacturing arts.

The inventors have discovered that a ceramic base material may bedamaged if an open structure within the ceramic base material is filledwith a material that includes too much abrasive material. The abrasivematerials may scratch, abrade, or otherwise damage the ceramic basematerial. Roofing products having the open structure of the ceramic basematerial filled with recycled roofing material that includes suchabrasive materials, typically in the form of roofing granules, mayprematurely fail a mechanical stress or other test, such as a tear test.In an embodiment, the roofing granules may be pulverized, crushed,ground, or otherwise reduced in size to form of a fine powder. Thus, theinventors have discovered that by filling the open structure of aceramic base material with a bituminous material having a low amount orsubstantially free of abrasive particles, a roofing product can beformed with recycled roofing material and still have acceptableproperties.

FIG. 1 includes a non-limiting, exemplary process flow that can be usedto form a roofing product that includes recycled roofing material. Themethod includes providing a ceramic base material, at block 102. Theceramic base material can be formed or obtained from a commerciallyavailable source. The ceramic base material can be vitreous ornon-vitreous and have an open structure. The open structure can allow abituminous material to flow within and partially or completely fill theopen structure. The open structure can be in the form of pores,channels, interstitial openings within a matrix, another suitable void,or any combination thereof. The open structure can be characterized asthe volume of the ceramic base material that is not occupied by aceramic material (e.g., glass fibers) and may be expressed as a matweight. In an embodiment, the mat weight can be at least approximately25 g/m² (0.5 lb/100 ft²), at least approximately 40 g/m² (0.8 lb/100ft²), or at least approximately 60 g/m² (1.2 lb/100 ft²). In anotherembodiment, the mat weight can be no greater than approximately 200 g/m²(4.0 lb/100 ft²), no greater than approximately 170 g/m² (3.5 lb/100ft²), or no greater than approximately 130 g/m² (2.7 lb/100 ft²). In aparticular embodiment, the mat weight can be in a range of approximately60 g/m² (1.3 lb/100 ft²) to approximately 120 g/m² (2.5 lb/100 ft²). Theceramic base material can include an oxide (e.g., silica, alumina,ceria, zirconia, or the like), a nitride (e.g., aluminum nitride,silicon nitride, or the like), a carbide (e.g., tungsten carbide,silicon carbide, or the like), or any combination thereof. In anembodiment, the ceramic base material includes fiberglass, and in aparticular embodiment, a fiberglass mat.

The method also includes preparing a bituminous material, at block 104.The bituminous material may be processed to achieve the desiredproperties. In an embodiment, asphalt, as received, can be oxidized toreduce the amount of volatile chemicals, partially polymerize a compoundwithin the asphalt, or a combination thereof. The process can be used toincrease the softening point of the asphalt to over approximately 90° C.(approximately 200° F.) or a penetration distance (100 g at 25° C., ASTMD5) of less than 18 to 22 dmm. In a particular embodiment, asphalt isoxidized by flowing pressurized air into a tank of asphalt heated toapproximately 230° C. (approximately 450° F.). For the purposes of thisspecification, asphalt as received or after the oxidation process, butbefore adding solids or chemicals, is referred to herein as virginasphalt.

The virgin asphalt and one or more other components can be combined.Such other components can include fillers, additive chemicals, othersuitable components, or the like. Fillers are relatively inert solidparticles and allow a relatively less expensive material to displacerelatively more expensive asphalt within the roofing product. As usedherein, filled virgin asphalt mixture refers to a combination of virginasphalt and one or more fillers. The filed virgin asphalt mixture may ormay not include additive chemicals or other components. In thebituminous material, the filler can include filler particles having ahardness that is less than the hardness of the ceramic base material.For example, when the ceramic base material includes a fiberglass mat,the filler particles can include limestone particles, and when theceramic base material includes alumina, the filler particles can includelimestone particles or sand. With respect to the fiberglass mat, thelimestone particles will not scratch the glass fibers, and therefore,will not significantly damage the fiberglass mat if the limestoneparticles and the glass fibers would contact each other. However, glasscan scratch glass, and therefore, sand may scratch the glass fibers ofthe fiberglass mat if the sand would contact the glass fibers. Unlike afiberglass mat, alumina is harder than glass, and therefore, a ceramicbase material including alumina will not be scratched by sand orlimestone particles.

Roofing granules can include materials that are harder than glass. Thus,roofing granules may scratch glass fibers within a fiberglass mat.Therefore, roofing granules are abrasive particles with respect to thefiberglass mat, and thus, may not be included in the bituminousmaterial. Still, a relatively small amount of abrasive particles may beused within the perimeter volume of a ceramic base material withoutcausing a substantial failure of the roofing product. In a particularembodiment, abrasive particles can be distributed within other materialthat is not as hard as the ceramic base material. For example, limestonecan be used as filler. Limestone is principally calcium carbonate;however, limestone may contain a relatively small amount of silica.Because the silica can be distributed throughout the limestone, verylittle of an already small amount of silica may be present along theperimeter of a limestone particle. Calcium carbonate within thelimestone would be disposed between most of the silica within thelimestone and the fiberglass mat, and thus, the calcium carbonate helpsreduce the likelihood that a significant amount of silica would contactthe fiberglass mat. In an embodiment, the bituminous material has nogreater than 5 weight % abrasive particles or no greater than 3 weight%. In another embodiment, the bituminous material has no greater than 1weight % abrasive particles, and in a further embodiment, the bituminousmaterial is substantially free of abrasive particles. More detailsregarding the roofing granules are described later in thisspecification.

For a ceramic base material that includes a fiberglass mat, in additionto limestone, the filler can include talc, clay, non-abrasive coalfines, gypsum, calcite, another similar material, or any combinationthereof. In a shingle embodiment, the bituminous material can include atleast approximately 45 weight % of filler, at least approximately 50weight % of filler, or at least approximately 55 weight % of filler. Inanother shingle embodiment, the bituminous material may include nogreater than approximately 80 weight % of filler, no greater thanapproximately 75 weight % of filler, or no greater than approximately 70weight % of filler. In a membrane embodiment, the bituminous materialmay include substantially no filler or may include at leastapproximately 5 weight % of filler, or at least approximately weight %of filler. In another membrane embodiment, the bituminous material mayinclude no greater than approximately 60 weight % of filler, no greaterthan approximately 50 weight % of filler, or no greater thanapproximately 40 weight % of filler. In a further embodiment, thebituminous material can include a higher or a lower filler content thanthe weight percents recited.

Additive chemicals that can be used with the bituminous material andinclude a process oil, a plasticizer, a polymer modifier, anothersuitable compound, or any combination thereof. The process oil caninclude a napthenic oil, an aliphatic oil, or an aromatic oil, anothersuitable oil, or any combination thereof. Another exemplary compound caninclude styrene-butadiene-styrene, styrene-ethylene-butylene-styrene,styrene-isoprene-styrene, acrylonitrile-butadiene-styrene, atacticpolypropylene, isotactic polypropylene, high density polyethylene,ethylene-polypropylene copolymer, another suitable plasticizer orpolymeric compound, or any combination thereof. A thermoplastic olefincan be formed using a metallocine catalyst and include a block copolymerpolypropylene, a polyethylene-propylene rubber, or another suitablematerial. Typically, the additive chemicals are in the form of solids orliquids at room temperature; however, the additive chemicals do notinclude asphalt, fillers, or roofing granules. For simplicity, theadditive chemicals are referred to herein in the plural even if only asingle chemical is used. In an embodiment, the bituminous material mayinclude substantially none of the foregoing additive chemicals, at leastapproximately 5 weight % of additive chemicals, or at leastapproximately 10 weight % of additive chemicals.

In another embodiment, the bituminous material may include no greaterthan approximately 40 weight % of additive chemicals, no greater thanapproximately 30 weight % of additive chemicals, or no greater thanapproximately 25 weight % of additive chemicals. In a furtherembodiment, the bituminous material can include a higher or a loweradditive chemical content than the weight percents recited.

The bituminous material may include recycled roofing articles (e.g.,membranes, shingles, roofer's felt, etc.). Recycled roofing articles caninclude post-industrial roofing articles, pre-consumer roofing articles,post-consumer roofing articles, or any combination thereof.Post-industrial roofing articles can include partially or completelymanufactured roofing articles that remain within the possession of themanufacturer. An example of a recycled roofing article can include apost-industrial roofing article that does not meet a productspecification. Post-consumer roofing articles can include roofingarticles that have been installed on a structure owned or controlled bya consumer, such as a homeowner or a business. Pre-consumer roofingarticles are completely manufactured roofing articles outside thepossession of the manufacturer and before the roofing articles areinstalled. An example of pre-consumer roofing articles can include abundle of shingles that is damaged by a shipping company or a roofingcontractor during shipping or handling, or obsolete products, such asroofing articles with outdated colors or designs, or expired products(e.g., a product that should not be installed on a roof due to age ofthe product).

If the recycled roofing articles do not have roofing granules or haveroofing granules that are not abrasive particles with respect to theceramic base material, the recycled roofing articles may replace asubstantial amount of asphalt within the bituminous material. If theroofing granules are abrasive particles with respect to the ceramic basematerial, recycled roofing articles may be used in the bituminousmaterial to the extent the roofing granules do not exceed the previouslyrecited weight % for abrasive particles, as described above with respectto fillers. In a particular embodiment, the bituminous material includesrecycled roofing articles that are substantially free of abrasiveparticles, and in another embodiment, the bituminous material issubstantially free of recycled roofing articles.

The components for the bituminous material are combined and heated to atemperature above the softening point of the virgin asphalt. Thecomponents can be first combined and then heated, or the asphalt can beheated, and then the other components can be added to the softenedasphalt. After reading this specification, skilled artisans appreciatethat the order of heating, combining or otherwise introducing componentsin forming the bituminous material can be chosen to meet the needs ordesires for a particular application. The bituminous material can beprepared in a conventional or proprietary apparatus used in preparingasphalt for use in roofing products.

The method also includes preparing a recycled roofing material, at block106. Many of the components within the recycled roofing material caninclude materials used for the bituminous material, and therefore, afocus of this activity is directed more to additional or differentactions that are taken with respect to the recycled roofing materials.

Roofing articles that are being recycled vary greatly with respect totime and exposure to different environmental conditions. Some roofingarticles may be recently scrapped, such as post-industrial roofingarticles that do not meet product specifications, and therefore, cannotbe sold as product. Post-industrial roofing articles can also includecut-outs from the shaping of the shingles during manufacturing (e.g.,the cut-outs may correspond to slots that were formed in a finishedthree-tab shingle). Other roofing articles may be pre-consumer roofingarticles that may have been stored at a warehouse or other locations formonths. Still other roofing articles may have been installed on astructure for years. Roofing articles may be post-consumer roofingarticles that may have been installed on different structures thatexperienced different environmental conditions. For example, roofingarticles installed on a structure exposed to more sun will have receivedmore ultraviolet radiation than roofing articles installed on adifferent structure exposed to less sun. As time elapses and effectiveexposure to ultraviolet radiation increases, the composition ofmaterials within the roofing articles can change. For example, volatilechemicals or plasticizers may be driven off or degraded, and furtherpolymerization of an asphalt material may occur.

Therefore, chemicals that will be used with recycled roofing materialcan include compounds that replace, replenish, or otherwise provide thesame or other compounds that have been volatilized or have becomedegraded. Such compounds can include the additive chemicals describedwith respect to the bituminous material. Thus, the additive chemicalsused in preparing the recycled roofing material can include a processoil, a plasticizer, a polymer modifier, another suitable compound, orany combination thereof. As compared to the bituminous material, theadditive chemicals may make up a larger fraction of the startingmaterials when preparing the recycled roofing material. In oneembodiment, virgin asphalt or filled virgin asphalt mixture can be usedin recycled roofing material, and in another embodiment, neither virginasphalt nor filled virgin asphalt mixture is used.

Unlike the bituminous material, abrasive particles are less of a concernwith the recycled roofing material. A significant fraction of therecycled roofing material can include roofing granules, sand, otherabrasive particles, or any combination thereof. The roofing granules mayhave a composition as described later in this specification. The roofinggranules, sand, or other abrasive particles can be as hard or harderthan the ceramic base material. In an embodiment, the recycled roofingmaterial may be substantially free of roofing granules, sand, and otherabrasive particles. Alternatively, the roofing granule, sand, or otherabrasive particle content within the recycled roofing material may be atleast approximately 2 weight %, 5 weight %, or 10 weight %, and inanother embodiment, the roofing granule, sand, or other abrasiveparticle content within the recycled roofing material may be no greaterthan approximately 50 weight %, 40 weight %, or 30 weight %.

The recycled roofing material may include wood, paper, fiberglass,polyester, or another material that may have been part of a basematerial used in shingles or a membrane as a roofing article.Alternatively, the recycled roofing materials may include one or moremetals from nails, flashing, or from metal fragments generated whenmaking the recycled material (e.g., fragments from steel balls orexposed surfaces within a mixing or grinding apparatus). These metalscan include iron, aluminum, copper, zinc, chromium, nickel, or the like,in elemental form (i.e., the metal element by itself and not part of acompound) or as part of an alloy. In an embodiment, the recycled roofingmaterial may be substantially free of the wood, paper, fiberglass,polyester, another base material, and metals content. In anotherembodiment, the wood, paper, fiberglass, polyester, another basematerial, or metal content within the recycled roofing material may beat least approximately 5 weight %, 10 weight %, or 15 weight %, and inanother embodiment, the wood, paper, fiberglass, polyester, other basematerial or metals content within the recycled roofing material may beno greater than approximately 30 weight %, 25 weight %, or 20 weight %.The metal content includes the relative amount of any and all metalsthat are in elemental or alloy form.

The recycled roofing material can include the following materials asstarting components for the recycled roofing material in the followingexemplary amounts. With respect to recycled roofing articles, in anembodiment, the recycled roofing article content may be at leastapproximately 5 weight %, 10 weight %, 15 weight %, or 20 weight %, andin another embodiment, the recycled roofing article content may be nogreater than approximately 95 weight %, 90 weight %, or 80 weight %.

With respect to virgin asphalt that is not part of the recycled roofingarticles, in an embodiment, substantially no virgin asphalt is added. Inanother embodiment, the virgin asphalt content may be at leastapproximately 10 weight % or 20 weight %, and in still anotherembodiment, the virgin asphalt content may be no greater thanapproximately 95 weight %, 90 weight %, or 80 weight %. With respect tofiller particles that are not part of the recycled roofing articles, ina particular embodiment, substantially no filler particles are present.In another embodiment, the filler particle content may be at leastapproximately 10 weight % or 20 weight %, and in another embodiment, thefiller particle content may be no greater than approximately 75 weight%, 60 weight %, or 50 weight %. With respect to additive chemicals thatare not part of the recycled roofing articles, in a particularembodiment, substantially no chemicals are added. In another embodiment,the additive chemical content may be at least approximately 5 weight %,10 weight %, or 15 weight %, and in another embodiment, the additivechemical content may be no greater than approximately 30 weight %, 25weight %, or 20 weight %. After reading this specification, skilledartisans will appreciate that any of the components may be present in anamount greater or less than approximately the amounts recited herein.

After the recycled roofing material has been generated, the recycledroofing material can have characteristics that are similar to thebituminous material and other characteristics that are substantiallydifferent from the bituminous material. Within the recycled roofingmaterial, the total asphalt content, virgin asphalt, asphalt fromroofing articles, or otherwise, may be at least approximately 10 weight% or 20 weight %, and in still another embodiment, the virgin asphaltcontent may be no greater than approximately 95 weight %, 90 weight %,or 80 weight %. With respect to total particle content (e.g., fromfiller, roofing granules, base material from roofing articles, etc.), ina particular embodiment, the recycled roofing material may havesubstantially no particles. In another embodiment, the total particlecontent may be at least approximately 10 weight % or 20 weight %, and inanother embodiment, the total particle content may be no greater thanapproximately 75 weight %, 60 weight %, or 50 weight %. In a particularembodiment, the recycled roofing material may have substantially noadditive chemicals. In another embodiment, the additive chemical contentwithin the recycled roofing material may be at least approximately 5weight %, 10 weight %, or 15 weight %, and in another embodiment, theadditive chemical content may be no greater than approximately 30 weight%, 25 weight %, or 20 weight %. After reading this specification,skilled artisans will appreciate that any of the components may bepresent in an amount greater or less than approximately the amountsrecited herein.

Many different materials have been described for use within the recycledroofing material. Any detectible amount of a residual material fromroofing articles, a roof, or equipment used to process recycled roofingmaterial can provide proof that recycled roofing material is presentwithin a roofing product. This residual material can include the roofinggranules or sand, a roofing article base material (e.g., fiberglass orpolyester mat, wood, paper, or the like), a roofing article coating(e.g., an acrylic material), a metal from roofing nails, wood from theroof decking (e.g., plywood), parts of a gutter, downspout, or screen, amaterial from grinding media (e.g., ceramic or steel balls) or a drumused in breaking down the roofing articles when processing the recycledroofing material, or any combination thereof. Thus, in a non-limitingembodiment, even 0.1 weight % of any of the residual materials within aparticular layer of a roofing product indicates that recycled roofingmaterial is present. In another embodiment, the residual roofingmaterials can be at least 1 weight % of a residual roofing material.

In an illustrative embodiment, the presence of recycled roofing materialcan be detected by determining the level of acid-insoluble solidsdisposed within a coating of a roofing product or a portion of suchcoating. Roofing granules and parting agents, such as sand, talc, or thelike, if present along the principal surfaces of the roofing product,are removed from the exposed surfaces of the roofing product. Theremaining coating of the roofing product or portion thereof is placed inan appropriate solvent to extract the bituminous material. One or moresolvents can be used, and the extraction can be performed as a singlewash or a series of washes. In a particular embodiment, a Soxhlet methodcan be used. After the bituminous material is removed, solids remain andinclude a mat (e.g., fiberglass, polyester, cellulose, etc.), filler,and solids from the recycled roofing material. If the particular coatingor portion thereof includes an embedded mat (e.g., fiberglass,polyester, cellulose, etc.) that is part of the base structure (that is,not residual pieces of a mat within the recycled roofing material), themat can be removed at this time to form remaining solids.

The remaining solids can then be further processed by disposing thesolids in an acid. Acid washing can be used to determine the presenceand amount of collateral abrasive content in nonabrasive fillers used inroofing materials. More particularly, limestone is primarily calciumcarbonate, and calcium carbonate can be dissolved in an HCl solution.Other materials, such as silica, roofing granules, and metals and metalsalloys, do not significantly dissolve in an HCl solution. Thus, bywashing the solids in the HCl solution, calcium carbonate from thelimestone is dissolved, and acid-insoluble solids remain. Theacid-insoluble solids can then be vacuum filtered onto a tared filterpaper. After drying and removing the filter paper, the acid-insolublesolids are typically silica, roofing granules, and metals and metalsalloys. When the filler principally includes a material other thancalcium carbonate, the selection of the acid can be changed to removethe other material while at least some other solids remain.

For a conventional roofing product having limestone filler, the amountof acid-insoluble solids is relatively low because a small amount of thelimestone may include silica or another similar material. A particularconventional roofing product that does not include any recycled roofingmaterial may have an acid-insoluble solids content of approximately 1.6%of the remaining solids. Thus, a conventional roofing product withoutany recycled roofing material has less than 2% of the remaining solids.

Clearly, a roofing product including recycled roofing material hassignificantly higher acid-insoluble solids content than a conventionalroofing product without any recycled roofing material. The recycledroofing material includes roofing granules, many of which are silicates,sand, residual fiberglass mat, metals or metal alloys from a grindingdrum or grinding media, or potentially other sources of acid-insolublematerials that may not be present in a conventional roofing product, orif present, at significantly lower levels. Therefore, a coating of aroofing product or portion of such coating including recycled roofingmaterial can have at least 2% acid-insoluble solids (as a percentage ofthe remaining solids), and in a particular embodiment, at least 3%acid-insoluble solids.

In a particular embodiment in which the coating or portion of suchcoating includes approximately 3 weight % recycled roofing content, theamount of acid-insoluble solids may be approximately 3.3% of theremaining solids. In another particular embodiment in which the coatingor portion of such coating includes approximately 6 weight % recycledroofing content, the amount of acid-insoluble solids may beapproximately 5.0% of the remaining solids. In still another particularembodiment in which the coating or portion of such coating includesapproximately 12 weight % recycled roofing content, the amount ofacid-insoluble solids may be approximately 8.4% of the remaining solids.Thus, the content of acid-insoluble solids provides a good indiciaregarding the presence and level of recycle roofing material within acoating of a roofing product or portion of such coating.

Particle size distribution may be an additional indicator that recycledroofing articles are present within a roofing product. A particle sizedistribution can have characteristic particle size. In a particularembodiment, the characteristic particle size can be an averaged particlesize, such as an average, a geometric mean, or a median. Alternatively,the characteristic particle size may be expressed as a percentile. Forexample, the characteristic particle size may be the particle size atthe 5^(th) percentile, 95^(th) percentile, or other percentile value.For a 95^(th) percentile value, the characteristic particle size wouldmean that 95 percent of all particles are a particular particle size orsmaller. In still another embodiment, the characteristic particle sizecan be the largest particle size of all the particles present. Inanother embodiment, the characteristic particle size may be determinedusing a different criterion.

In a particular embodiment, the characteristic particle size of therecycled roofing material is smaller than the characteristic particlesize of conventional asphalt shingles or the bituminous material, aspreviously described. In a particular embodiment, the characteristicparticle size of the recycled roofing material is no more than 70%, 50%,or 30% of the characteristic particle size of conventional asphaltshingles or the bituminous material.

FIG. 2 includes an illustration of a particle size distribution ofconventional limestone filler within an asphalt coating as measured by aCoulter counter, and FIG. 3 includes an illustration of a particle sizedistribution within a recycled roofing material. The recycled roofingmaterial can be prepared using a Union Process Attritor Model 1-S,approximately 9 mm (⅜ inch) grinding media and a rotational speed ofbetween 100 to 650 rotations per minute.

In this particular embodiment, the characteristic particle size can be amedian particle size or the size at the 5^(th) or 95^(th) percentile.Referring to FIG. 2, for the conventional limestone filler, the medianparticle size is 44 microns with 5^(th) and 95^(th) percentiles at 1.4and 260 microns, respectively. Referring to FIG. 3, for the recycledroofing material, the median particle size is 14 microns (about ⅓ themedian particle size of the conventional limestone filler), and the5^(th) and 95^(th) percentiles at 1.8 and 81 microns, respectively.Thus, the recycled roofing material can have a narrower distribution ofparticle size as compared to conventional limestone filler or thepreviously described bituminous material. In another embodiment, adifferent apparatus, a different size of grinding media, a differentrotational speed, or any combination thereof can be used to prepare therecycled roofing material. Thus, a smaller median particle size and aneven tighter distribution of particle sizes may be achieved.

In another embodiment, the particle size distribution of particles in acoating can include a plurality of modes, wherein a particular mode isindicative of recycled material, another particular mode is indicativeof a conventional filler, a further particular mode is indicative offilled virgin asphalt mixture or other fresh content, or any combinationthereof. For example, one of the modes may correspond to a particle sizedistribution as illustrated in FIG. 3. In still another embodiment, anysignificant deviation from the particle size distribution in FIG. 2 mayalso be indicative of recycled roofing material being present.

Any of the components for the recycled roofing material can be initiallyprocessed before such component is used. For example, recycled roofingarticles may have roofing nails or other undesired items removed.Recycled roofing articles may or may not be cut or shredded to reducethe individual sizes of the roofing articles. In one particularembodiment, recycled roofing articles are reduced in size to dimensionsof about 10 cm×15 cm (4″×6″) prior to adding to the media mixer. Inother embodiments, the recycled roofing articles may be larger orsmaller in size. The virgin asphalt, or filled virgin asphalt mixture,or chemicals may be preheated. Other initial processing may be performedas needed or desired.

The process used in preparing the recycled roofing material may becarried out as a batch or continuous operation. The processing apparatusmay include steel balls, ceramic grinding media, or other items that mayhelp to break up the recycled roofing articles into smaller pieces. In aparticular embodiment, virgin asphalt or filled virgin asphalt mixturecan be heated above its softening point. Additive chemicals can becombined with the virgin asphalt before or after the virgin asphalt orfilled virgin asphalt mixture is above its softening point. Recycledroofing articles can be combined with the heated virgin asphalt orfilled virgin asphalt mixture and potentially additive chemicals. Ifneeded or desired, additional filler particles can be added to achieve adesired particle content for the recycled roofing material. In anotherparticular embodiment, all components for the recycled roofing materialcan be combined within the apparatus before or after heating. In stillanother particular embodiment, a different order of adding thecomponents may be used. After reading this specification, skilledartisans will appreciate that the order in which components are firstcombined can be tailored to the particular needs or desires for aparticular apparatus and application. The recycled roofing material canbe in a softened state and optionally may be filtered or magneticallyseparated during or after preparing the recycled roofing material toremove roofing nails or other undesired items.

Recycled roofing articles can be ground within a media mixer. In aparticular embodiment, the media mixer is an attritor that includes amixing vessel, mixing media, and an agitator. The mixing vessel, mixingmedia, agitator, and virgin asphalt are heated to approximately 210° C.(approximately 400° F.), with the agitator rotating at approximately 100revolutions per minute (rpm) for approximately 5 minutes. After mixingmedia and virgin asphalt or filled virgin asphalt mixture have beenmixed, recycled roofing articles can be added.

Before adding the recycled roofing articles, the amount of recycledroofing articles to be added can be determined in order to achieve adesired amount of filler (solids) that is to be present within themixture. The roofing articles can include parts of fiberglass mats,roofing granules, sand or talc (from parting agents), limestone, or anycombination thereof. If the mixture is to include approximately 50weight % filler, the mixture can include approximately 40 weight %virgin asphalt or virgin asphalt mixture and approximately 60 weight %recycled roofing articles. As the desired amount of filler orcomposition of the recycled roofing articles within the mixture changes,the relative amounts of virgin asphalt and recycled roofing articles canlikewise change.

The recycled roofing articles can be added all at once into the vesselor may be added in segments. When the mixture includes approximately 60weight % recycled roofing articles, the recycled roofing articles can beadded in two (halves) or three (thirds) different stages, with eachstage having approximately the same amount of recycle roofing articles.During each stage, the agitator can be stopped and the desired amount ofrecycled roofing articles can slowly be added. The mixture can be mixedwith the agitator rotating at approximately 100 rpm for approximately 1minute, and then the rotational speed of the agitator can be increasedto approximately 350 rpm for approximately 1 minute. The process can beiterated for the remainder of the stages until all of the recycledroofing articles are added.

After all of the recycled roofing articles have been mixed as describedabove, the resulting mixture can be mixed with the agitator at arotational speed of approximately 350 rpm for approximately 20 minutesto form a ground mixture. Throughout the process, the temperaturesetpoint can remain at approximately 210° C. (approximately 400° C.).The ground mixture can then be drained or otherwise removed from thevessel. The ground mixture may have the particle size distribution asillustrated in FIG. 3. While the process has been described with respectto an attritor, skilled artisans will appreciate that other equipmentand processes can be used to produce the ground mixture. For example, arotating ball mill is another media mixer that can be used in formingthe ground mixture.

Table 1 includes properties of three different batches of the groundmixture. In Table 1, the softening point is determined using ASTMD-36-06, the viscosity is determined using ASTM D-4402-06, thepenetration is determined using ASTM D-5 as described in ASTM D-449-03,and the stain test is determined using ASTM D-2746-07. As used in thetables in this specification, “Total Solids” refers to solids contentafter asphalt is removed.

TABLE 1 Target Grind 1 Grind 2 Grind 3 Softening Point (° F.) 134 136136 Viscosity (cps) @ 300° F. 875 1050 1075 325° F. 500 575 588 350° F.250 350 363 Penetration (dmm)  77° F. 38 35 37 115° F. 176 170 162Remaining Solids (wt %) 50% 45.7 47.0 47.7 Acid-Insoluble Solids 55%50.8 50.0 51.1 (% of Remaining Solids) Stain ( 1/64 s of an inch) 11.5 87.5

Information in the Table 1 can be expressed in metric units. Thesoftening point of Grinds 1, 2, and 3 are approximately 57° C., 58° C.,and 58° C., respectively. The temperatures for determining theviscosities are approximately 149° C., 163° C., and 177° C., and thetemperatures for determining the penetrations are approximately 25° C.and 46° C. The stain distance of Grinds 1, 2, and 3 are approximately4.6 mm, 3.2 mm, and 3.0 mm, respectively.

In other embodiments, different levels of total solids content can bedifferent for the ground mixture. The amount of virgin asphalt added maybe adjusted to achieve a desired total solids content, viscosity, orboth.

In an embodiment, the ground mixture can be used as a recycled roofingmaterial. In another embodiment, another material may be added to reducethe recycled content for the recycled roofing material. A filled virginasphalt mixture can include virgin asphalt, limestone or other fillers,and potentially additive chemicals. A combination of the filled virginasphalt mixture and the ground mixture can be combined to form therecycled roofing material. In a particular embodiment, the recycledroofing material can include approximately 5 weight % of the groundmixture with the remainder substantially the filled virgin asphalt mix(recycled roofing material is approximately 3% recycled roofingcontent). In another embodiment, the recycled roofing material caninclude approximately 10 weight % of the ground mixture with theremainder substantially the filled virgin asphalt mixture (recycledroofing material is approximately 6% recycled roofing content). In yetanother embodiment, the recycled roofing material can includeapproximately 20 weight % of the ground mixture with the remaindersubstantially the filled virgin asphalt mixture (recycled roofingmaterial is approximately 12% recycled roofing content). In still otherembodiment, part or all of the virgin asphalt can be replaced bystyrene-butadiene-styrene (SBS) or another polymer. In a particularembodiment, 10 weight % SBS can be used.

Table 2 below includes data for a roofing product that includes afiberglass mat that is filled with filled virgin asphalt mixture(control), 10 weight % ground mixture with the remainder filled virginasphalt mixture (10% mixture), and 20 weight % ground mixture with theremainder filled virgin asphalt mixture (20% mixture). Tests asdescribed with respect to Table 1 can be used to obtain the data inTable 2. In addition, the tear test can be determined using ASTM D-1922as modified in D-228-08.

TABLE 2 10% 20% Target Control mixture mixture Softening Point (° F.)205-225 226 212 197 Viscosity (cps) 350° F. 1500-3000 4188 3000 1800375° F. 2000 1580 988 400° F. 1138 875 625 Penetration (dmm)  77° F. 711 13 115° F. 15 18 25 Remaining Solids (wt %) 50% 55.5 55.2 53.3Acid-Insoluble Solids (% of 1.63 6.62 11.01 Remaining Solids) % recycleadded based on 10.3 19.4 acid-insoluble solids Stain ( 1/64 s of aninch) 5.5 6.5 6.3 Tear Test (g) CD 1700 1800 1400 1300 MD 1300 1100 1000

Information in the Table 2 can be expressed in metric units. Thesoftening point of Control, 10% mixture, and 20% mixture areapproximately 108° C., 100° C., and 92° C., respectively. Thetemperatures for determining the viscosities are approximately 177° C.,191° C., and 204° C., and the temperatures for determining thepenetrations are approximately 25° C. and 46° C. The stain distance ofControl, 10% mixture, and 20% mixture are approximately 2.2 mm, 2.6 mm,and 2.5 mm, respectively.

The target for total solids is 50 weight %. The control, 10% mixture,and the 20% mixture have a solids content of about 53 to 56 weight %solids. Clearly, the acid-insoluble solids content increases with ahigher amount of ground mixture. Thus, the control has about 1.6% acidinsoluble solids, the 10% mixture has approximately 6.6% acid insolublesolids, and the 20% mixture has approximately 11% acid insoluble solids.Solely by using the acid-soluble solids and knowing the composition ofthe filled virgin asphalt mixture and the ground mixture within therecycled roofing material, the ground mixture content within therecycled roofing material can be calculated (“% recycle added based onacid-insoluble solids” in Table 2). The 10% mixture is calculated to beapproximately 10 weight % ground mixture, and the 20% mixture iscalculated to be approximately 19 weight % ground mixture. Thus,acid-insoluble solids content can be used not only to determine thepresence or absence of recycled roofing material, but it can also beused to estimate the amount of ground mixture within the recycledroofing material.

Viscosity decreases and penetration distance increases with increasingthe ground mixture content. Stain distance is not significantly affectedby the increased ground mixture content.

Particularly noteworthy is the tear strength. The tear test is performedin the machine direction (MD), which is substantially parallel to thedirection in which the roofing product is principally moved duringmanufacturing, and the cross direction (CD), which is perpendicular tothe machine direction. The tear strength in both directions decreaseswith an increasing ground mixture content. With respect to CD, the tearstrength of the control roofing product is approximately 1800 grams,which is above the specification of 1700 grams. However, the tearstrength decreases to 1400 and 1300 grams for the 10% mixture and the20% mixture, respectively. The solids from recycled roofing articles caninclude abrasive particles that are believed to fracture or scratch thefiberglass mat and lead to premature tearing in the MD and CD at levelsbelow that seen with the control.

Table 3 below include data for a roofing product similar to the roofingproduct in Table 2, except that the fiberglass mat is replaced with apolyester mat and the filled virgin asphalt mixture includes 10 weight %of SBS polymer. The tear test for the roofing products in Table 3 wasperformed as a notched tear in order to initiate tearing. This tear testcan be determined using ASTM D-4073, as modified in ASTM D-5147-07b.

TABLE 3 10% 20% Target Control mixture mixture Softening Point (° F.)260-290 256 255 247 Viscosity @ 350° F. 4375 4375 3625 (cps) 375° F.2800-4200 3000 2350 1825 400° F. 2300 1600 1300 Penetration (dmm)  77°F. 40-50 39 29 30 115° F. 78 64 67 Remaining Solids (wt %) 30.0% 27.4%31.2% 33.6% Acid-Insoluble Solids (% of 1.61 12.1 20.8 Remaining Solids)% recycle added based on 13.0% 25.7% acid-insoluble solids Stain ( 1/64s of an inch) 3 3 4 Tear Test (lbf) CD 55 75 70 70 MD 55 120 110 120

Information in the Table 3 can be expressed in metric units. Thesoftening point of Control, 10% mixture, and 20% mixture areapproximately 124° C., 124° C., and 119° C., respectively. Thetemperatures for determining the viscosities are approximately 177° C.,191° C., and 204° C., and the temperatures for determining thepenetrations are approximately 25° C. and 46° C. The stain distance ofControl, 10% mixture, and 20% mixture are approximately 1.2 mm, 1.2 mm,and 1.6 mm, respectively.

Many of the trends seen with the roofing products in Table 3 are similarto those seen with the roofing products in Table 2. However, the trendseen with the tear test for the roofing products in Table 3 differs fromtrend seen with the tear test for the roofing products in Table 2. Thetear strength of the roofing products with recycled roofing material issimilar to the tear strength of the roofing product without any recycledroofing material. Therefore, abrasive particles, which can scratchglass, do not have a significantly adverse affect on the roofingproducts that include a polyester mat for a base material.

In summary, with respect to preparation of the recycled roofingmaterial, at block 106 of FIG. 1, many different materials, content ofthose materials, particular actions in preparing the recycled roofingmaterial, or any combination thereof are disclosed. After reading thisspecification, skilled artisans will appreciate that preparing therecycled roofing material can be modified to include other materials,content of those materials, particular actions in preparing the recycledmaterial, or any combination thereof to meet the needs or desires for aparticular application.

Before continuing with the method as illustrated in FIG. 1, exemplary,non-limiting apparatuses for manufacturing roofing products areillustrated in FIGS. 4 and 6 that will be described with respect to theremainder of the method in the embodiment as illustrated in FIG. 1. Anapparatus 200 in FIG. 4 is particularly suited for manufacturing ashingle-type roofing product 210, a cross-sectional view of which isillustrated in FIG. 5. An apparatus 400 in FIG. 6 is particularly suitedfor manufacturing a membrane-type roofing product 410, a cross-sectionalview of which is illustrated in FIG. 7. After reading thisspecification, skilled artisans will appreciate that the apparatuses 200and 400 and the manufacturing operations described herein are simplifiedto improve the understanding of the concepts as described herein. Otherequipment, process controls, and other features and operations may bepresent or performed in order to manufacture a commercial roofingproduct.

Referring to the embodiment as illustrated in FIG. 4, the apparatus 200includes tanks that contain the bituminous material 220 and the recycledroofing material 230 and 250, all of which are in a softened state. Theapparatus 200 also includes a hopper 262 that dispenses roofing granules260, and a hopper 272 that dispenses a parting agent 270. In theembodiment of FIG. 4, after the parting agent 270 is applied, a stampingor cutting operation (illustrated as box 280) is performed to form thefinished roofing product 210 in the form of shingles. Rollers 221, 222,223, 224, 231, 232, 241, 242, 243, 244, 245, 246, 247, 251, and 252 helpto guide the roofing product, apply a coating or a layer onto theroofing product, perform another suitable function, or any combinationthereof. Subsequent paragraphs provide more details regarding theoperation of the apparatus 200 in forming the finished roofing product210. Such details are to illustrate particular embodiments and not tolimit the present invention. In another embodiment, more or fewer partsof the apparatus can be used. After reading the specification, skilledartisans will be able to determine a configuration of the apparatus tomake a particular roofing product.

Referring to FIG. 1, the method includes filling the open structure ofthe ceramic base material with the bituminous material, at block 122. Asillustrated in FIG. 4, a ceramic base material 201 can be fed to theapparatus 200. The rollers 221, 222, 223, and 224 help to guide theceramic base material 201 during a bituminous material stage 22. Theopen structure of the ceramic base material 201 becomes filled by thebituminous material 220 to form a saturated base material 202. In aparticular embodiment, the open structure within the ceramic basematerial 201 is filled with the bituminous material 220 as it issubmerged into the bituminous material 220. In another embodiment (notillustrated), the open structure of the ceramic base material 201 can befilled by spraying or coating the bituminous material 220 onto theceramic base material 201. Because the bituminous material 220 can havea relatively low abrasive particle content or be substantially free ofabrasive particles, the likelihood that the ceramic base material 201becomes scratched or abraded during the bituminous material stage 22 isreduced and may be substantially eliminated. If too many undesiredscratches or abrasions would be formed, they may result in a failure ofthe ceramic base material 201 during subsequent mechanical stress duringmanufacturing, shipping and handling, installation, an in-use stress,such as thermal expansion or contraction after the roofing product isinstalled on a roof, or any combination thereof. The roller 224 can actas a metering roller to help reduce the likelihood that excessbituminous material 220 will exit the bituminous stage 22 with thesaturated base material 202.

With respect to the saturated base material 202, the open structure ofthe ceramic base material 201 may be substantially completely filledwith the bituminous material 220. The outermost portions of the ceramicbase material 201 within the saturated base material 202 may or may notbe exposed. In an embodiment, the volume of the bituminous material 220is greater than a perimeter volume of the ceramic base material 201, andin another embodiment, the volume of the bituminous material 220 is nogreater than the perimeter volume of the ceramic base material 201. In aparticular embodiment, with respect to the ceramic base material 201within the saturated base material 202, a portion of a principal surfaceof the ceramic base material 201 may be exposed; however, most of thestructure or volume of the ceramic base material is embedded within orsaturated with the bituminous material 220. Thus, if the ceramic basematerial 201 is scratched or abraded at this point or later in theprocess, such a scratch or an abrasion will have a lesser effect on theproperties of the finished roofing product, as compared to a roofingproduct where a substantial amount of abrasive particles would liewithin interior portions of the open structure (e.g., when a substantialamount of abrasive particles, e.g., fine roofing granules, sand,fiberglass mat particles, etc., from recycled roofing articles would beused in the bituminous material 220).

The method further includes applying the recycled roofing material afterfilling the open structure, at block 124. The saturated base material202 can have a layer of the recycled roofing material 230 applied duringa recycled roofing material stage 23 to form an intermediate roofingproduct 203. The layer including the recycled roofing material 230 maybe applied to a principal surface of the saturated base material 202 toform an intermediate roofing product 203. As previously discussed, therecycled roofing material 230 can include a significant amount ofabrasive particles. Thus, the bituminous material 220 can substantiallyprevent the abrasive particles from the recycled roofing material 230from reaching the center of the ceramic base material 201 within theintermediate roofing product 203. In a particular embodiment wherein theceramic base material 201 is substantially completely embedded orsaturated with the bituminous material 220, the abrasive particles maynot contact the ceramic base material 201 when forming the intermediateroofing product 203, and thus, substantially prevent scratching orabrading of the ceramic base material 201 during manufacturing orsubsequent handling or use.

A determination is made whether one or more additional coatings are tobe applied, at decision tree 142. If yes, the additional coating(s) maybe applied to the same, a different, or both principal surfaces of theintermediate roofing product 203, at block 144 in FIG. 1. Referring toFIG. 4, rollers 241 and 242 help to invert the intermediate roofingproduct 203. During recycled roofing material stage 25, a coating of arecycled roofing material 250 is applied along the opposite principalsurface of the intermediate roofing product 203 (as compared to therecycled roofing material 230) to form an intermediate roofing product204. The recycled roofing material 250 may be the same or different fromthe recycled roofing material 230. Similarly to the recycled roofingmaterial 230, the recycled roofing material 250 can include asignificant amount of abrasive particles. Thus, the bituminous material220 can substantially prevent the abrasive particles from the recycledroofing material 250 from reaching the center of the ceramic basematerial 201 within the intermediate roofing product 204. In aparticular embodiment wherein the ceramic base material 201 issubstantially completely embedded or saturated with the bituminousmaterial 220, the abrasive particles may not contact the ceramic basematerial 201 when forming the intermediate roofing product 204, andthus, substantially prevent scratching or abrading of the ceramic basematerial 201 during manufacturing or subsequent handling or use.

In another embodiment, other additional layer(s) can include thebituminous material 220, the recycled roofing material that is the sameor similar to the recycled roofing material 230 or 250, another suitablematerial or compound, or any combination thereof. After reading thisspecification, skilled artisans can determine whether additionalcoating(s) are needed or desired and the composition of such otheradditional coating(s).

After additional coating(s) are applied or if no additional coating isapplied (“No” branch of decision tree 142), the method can includefinish processing of the roofing product, at block 162. Referring toFIG. 4, a finishing stage 26 can include one or more operations. In anembodiment, a hopper 262 can dispense roofing granules 260 onto theintermediate roofing product 204 to form a substantially completedroofing product 205.

The roofing granules 260 can be used for ultraviolet radiationprotection, coloration, impact resistance, fire resistance, anothersuitable purpose, or any combination thereof. The roofing granules 260can include inert base particles that are durable, inert inorganicmineral particles, such as andesite, boehmite, coal slag, diabase,metabasalt, nephaline syenite, quartzite, rhyodacite, rhyolite, rivergravel, another suitable inert material, or any combination thereof.

The roofing granules 260 can also include one or more coatings over theinert base particles. A coating layer can cover at least approximately75% of the surface of the inert base particle, and may cover at leastapproximately 90% of the surface of the inert base particle. In aparticular embodiment, the coating continuously covers the surface ofthe inert base particle, and such coating layer has a substantiallyuniform thickness. If more than one coating is used, a subsequentcoating may cover an underlying coating to the extent described withrespect to the inert base particles.

If more than one coating is used, a coating closer to the inert baseparticles can include a binder that can be inorganic or organic. Aninorganic binder can include a silicate binder, a titanate binder, azirconate binder, an aluminate binder, a phosphate binder, a silicabinder, another suitable inorganic binder, or any combination thereof.An organic binder can include a polymeric compound. In a particularembodiment, an organic binder can include an acrylic latex,polyurethane, polyester, silicone, polyamide, or any combinationthereof. One or more additional organic binders of the same or differentcomposition can be used.

A coating can include an algaecide or another biocide to help reduce ordelay the formation of algae or another organic growth. The algaecide orother biocide can include an organic or inorganic material. Thealgaecide or other biocide can include a triazine, a carbamate, anamide, an alcohol, a glycol, a thiazolin, a sulfate, a chloride, copper,a copper compound, zinc, a zinc compound, another suitable biocide, orany combination thereof. In a particular embodiment, the algaecide orother biocide can be included within a polymeric latex binder. Thepolymeric latex binder can include polyethylene, another polyolefin, anacid-containing polyolefin, ethylene vinyl acetate, an ethylene-alkylacrylate copolymer, a polyvinylbutyral, polyamide, a fluoropolymer, anacrylic, a methacrylate, an acrylate, polyurethane, another suitablebinder material, or any combination thereof. Alternatively, the bindermay be a solvent-based coating, a radiation curable coating, or atwo-part reactive coating. These alternative coatings may likewiseinclude any of previously described polymeric materials. The same ordifferent algaecide or other biocide can be used within differentcoatings. An algaecide or another biocide is not required to be presentin every coating of the roofing granules. In another particularembodiment, the algaecide or other biocide can be an inorganic materialthat is included within an inorganic binder, for example, within analkali metal silicate binder. An exemplary inorganic algaecide or otherbiocide can include a metal (by itself), a metal oxide, a metal salt, orany combination thereof. The metallic element used within the metal,metal oxide, or salt may include copper, zinc, silver, or the like. Themetal salt can include a metal sulfate, a metal phosphate, or the like.

A coating can include a solar reflective material that helps to reflectat least some of the solar energy. For example, UV radiation can furtherpolymerize or harden the roofing product being made. A solar reflectivematerial can include titanium dioxide, zinc oxide, or the like.Alternatively, the solar reflective material can include a polymericmaterial. In an embodiment, a polymer can include a benzene-modifiedpolymer (e.g., copolymer including a styrene and an acrylate), afluoropolymer, or any combination thereof. Other solar reflectivematerials are described in U.S. Pat. No. 7,241,500 and U.S. PublicationNos. 2005/0072110 and 2008/0220167, all of which are incorporated byreference for their teachings of materials that are used to reflectradiation (e.g., UV, infrared, etc.) from the sun.

A coating can include a colorant or another material to provide adesired optical effect. The colorant or other material can include ametal oxide compound, such as titanium dioxide (white), zinc ferrite(yellow), red iron oxides, chrome oxide (green), and ultramarine (blue),silver oxide (black), zinc oxide (dark green), or the like. In anotherembodiment, the colorant or other material may not be a metal-oxidecompound. For example, the colorant may include carbon black, zinc oraluminum flake, or a metal nitride.

An additional coating may be used for a different purpose not describedherein. For example, the coating can include a different oxide, nitride,oxynitride, carbide, or any combination thereof. After reading thisspecification, skilled artisans will be able to determine if anadditional function or purpose is to be served by the roofing granulesand whether an existing coating or material within a coating serves sucha function or purpose or if an additional coating or an additionalmaterial within an existing coating would be needed or desired.

More than one type of roofing granule can be used in a roofing product.Thus, roofing granules can have a characteristic hardness. The hardnessof each roofing granule can be the hardness of the material along anexposed surface of the roofing granule. If no coating is used, thehardness of a particular roofing granule can be the hardness of theinert base particle for that particular roofing granule. If a coating isused, the hardness of the particular roofing granule can be the hardnessof the coating lying along the exposed surface of that particularroofing granule. For a set of roofing granules, the characteristichardness can be an averaged hardness, such as an average, a geometricmean, or a median. Alternatively, the characteristic hardness may beexpressed as a percentile. For example, the characteristic hardness maybe a 10^(th) percentile, 25^(th) percentile, or other percentile value.For a 10^(th) percentile value, the characteristic hardness would meanthat 10 percent all other roofing granules are as hard or harder than aparticular hardness. In still another embodiment, the characteristichardness can be the highest hardness for the roofing granules within theset. In another embodiment, the characteristic hardness may bedetermined using a different criterion.

In an embodiment, the roofing granules 260 can make up at leastapproximately 5 weight %, 8 weight %, or 11 weight % of thesubstantially completed roofing product 205, and in another embodiment,the roofing granules 260 may make up no greater than approximately 60weight %, 50 weight %, or 45 weight % of the substantially completedroofing product 205.

In addition to or in place of applying roofing granules 260, anotherfinishing operation can be performed. For example, after the roofinggranules 260 are applied, another coating (not illustrated), similar toany single or combination of binders and coatings previously describedwith respect to the roofing granules 260, may be coated onto the roofingproduct after roofing granules 260 have been applied. Such binder orcoating may have a solar reflective property, an algaecide or otherbiocide, a pigment or another appearance modifier, or any combinationthereof as previously described.

Rollers 243, 244, and 245 help to invert the substantially completedroofing product 205. In another finishing stage 27, a hopper 272 candispense a parting agent 270 onto the substantially completed roofingproduct 205. The parting agent 270 helps to keep the roofing productfrom sticking to itself or sticking to other manufacturing equipment,such as the equipment used in the stamping or cutting operation. Theparting agent 270 can include particles of sand, talc, limestone, slag,another relatively inert material, or any combination thereof. Afterapplying the parting agent 270, the roofing product can be processedduring a stamping or cutting operation, illustrated as box 280 in FIG.4, to achieve a desired shape for a finished roofing product 210. Inparticular, the finished roofing product 210 is in the form of shinglesin the embodiment of FIG. 4.

In still another embodiment, no finishing operation may be performed,only one or some, but not all, of the previously-described finishingoperations may be performed, or another finishing operation may beperformed in addition to or in place of another finishing operation aspreviously described. Alternatively, the take-up roll may be usedinstead of or before performing the stamping or cutting operation 280.After reading this specification, skilled artisans will be able toconfigure a manufacturing line for the particular roofing product beingformed.

FIG. 5 includes an illustration of a cross-sectional view of thefinished roofing product 210. The finished roofing product 210 includesthe saturated base material 202, which includes the ceramic basematerial 201 (not separately illustrated in FIG. 5) having an openstructure that is filled with the bituminous material 220 (notseparately illustrated in FIG. 5). The recycled roofing material 250 isdisposed between the saturated base material 202 and the parting agent270, and the recycled roofing material 230 is disposed between thesaturated base material 202 and the roofing granules 260. In theembodiment as illustrated in FIG. 5, roofing granules 260 are disposedalong one principal surface of the finished roofing product 210, and theparting agent 270 is disposed along the other principal surface of thefinished roofing product 210.

In another embodiment, a membrane-type roofing product can bemanufactured. FIG. 6 includes the apparatus 400 used to manufacture themembrane-type roofing product. The membrane-type roofing product hassignificant differences in the manufacturing process because themembrane-type roofing product is typically a self-adhesive product,although this is not a requirement. Still, the manufacturing processused for making membrane-type roofing products may be similar to themanufacturing process used for making shingle-type roofing products.

Referring to a particular non-limiting embodiment as illustrated in FIG.6, the intermediate product 204 is manufactured using the apparatus 400in a manner similar to the manufacturing process previously describedwith respect to the apparatus 200 in FIG. 4.

The finishing operations for a membrane-type roofing product can varydepending on the particular application. In a particular embodiment, aprincipal surface of the membrane-type roofing product can be directlyexposed to an outdoor environment. For this particular application,roofing granules, a coating, or both may be used. When the membrane-typeroofing product is used as part of an underlayment or as a lower layerof a built-up roofing system, roofing granules may not be used. Themembrane-type roofing product may be applied directly to a roof deck asa base sheet or an underlayment. In this particular application, anadhesive can be used to provide a good seal to help reduce thelikelihood of water damage from ice dams.

Referring to the apparatus 400 in FIG. 6, the finishing operationincludes applying adhesive and a release sheet to the intermediateroofing product 204. The apparatus 400 includes an adhesive applicator460 that applies an adhesive (not illustrated) to the intermediateroofing product 204 to form an adhesive roofing product 405. Theadhesive can include a tackifier, such as polyvinylbutyral, a pressuresensitive adhesive, another suitable compound, or any combinationthereof. A pressure sensitive adhesive can include a silicone, a rubber,an acrylate, a bituminous adhesive, or the like. In a particularembodiment, a styrene-isoprene-styrene rubber composition can be used. Arelease sheet 470 can be dispensed from a supply roll 471 to theadhesive side of the adhesive roofing product 405 at a roller 472 toform a finished roofing product 410. In the embodiment as illustrated inFIG. 6, the finished roofing product 410 is received by the take-up roll480.

In an alternative embodiment (not illustrated), an adhesive modifier canbe added to the recycled roofing material 250, and thus eliminate aseparate adhesive application operation. In this particular embodiment,the release sheet 470 would be applied to the surface having theadhesive-modified recycled roofing material.

FIG. 7 includes an illustration of a cross-sectional view of thefinished roofing product 410. The finished roofing product 410 includesthe saturated base material 202, which includes the ceramic basematerial 201 (not separately illustrated in FIG. 7) having an openstructure that is filled with the bituminous material 220 (notseparately illustrated in FIG. 7). The recycled roofing material 230 isdisposed between the saturated base material 202 and the release sheet470, and the recycled roofing material 250 is exposed along the oppositeside of the saturated base material 202. In the embodiment asillustrated in FIG. 7, recycled roofing material 250 is disposed alongone principal surface of the finished roofing product 410, and therelease sheet 470 is disposed along the other principal surface of thefinished roofing product 410. In another embodiment not shown in FIG. 7,granules are included on top of the layer of recycled material 250. Inyet another embodiment, a film is laminated to the top surface of thelayer of recycled material 250.

After reading this specification, skilled artisans will appreciate thatmany other roofing products can be made using the concepts as describedherein. The particular materials, layer, processes, and other parameterscan be tailored for the roofing products that are needed or desired.

The embodiments as described herein can be used to produce a roofingproduct that includes a ceramic base material and recycled roofingmaterial with acceptable properties. In an embodiment, a roofing producthaving a relatively low content of or substantially no abrasiveparticles within the open structure of a ceramic base material can stillinclude recycled roofing material and have good tear resistance. Byhaving a relatively low or no abrasive particle content within a filledceramic base material, the likelihood of a fracture or a scratch formingwithin the inner portion of the ceramic base material is significantlyreduced, and therefore, less likely to fail when put under stress. Thus,the tear strength of the roofing product as described herein can becloser to a roofing product that does not include any recycled roofingmaterial than a roofing product that includes abrasive particles withinthe matrix of the ceramic base material.

More particularly, the roofing product as described herein can have atear strength that is as good as or no less than approximately 70% ofthe tear strength of a roofing product that does not include anyrecycled content. In a particular embodiment, the roofing product asdescribed herein can have a tear strength that is no less thanapproximately 80% or approximately 90% of the tear strength of a roofingproduct that does not include any recycled roofing material. As acomparison, a roofing product with recycled roofing material deeplyembedded or saturated within the open structure of a ceramic basematerial may have a tear strength that is only approximately 60% of thetear strength of a roofing product without any recycled content.

The embodiments can be used to help reduce waste. By recycling roofingarticles, the roofing articles may be used to make new roofing products,rather than occupying valuable space within a landfill. Because roofingarticles biodegrade relatively slowly, any reduction of roofing articlesin a landfill helps the environment. Still further, roofing productsproduced with recycled roofing material may be less costly to produce.With the price of crude oil increasing, the price of virgin asphaltincreases at the same time or shortly thereafter. Unlike virgin asphalt,the price of the roofing articles may slowly increase as environmentalconcerns may force scrapped roofing articles to be recycled. Thus,embodiments as described herein allow roofing products to be made at alower cost as compared to roofing products formed without any recycledroofing articles.

Example

The concepts described herein will be further described in the Example,which does not limit the scope of the invention described in the claims.The Example demonstrates that the tear strength of a roofing product canbe improved by controlling the location of recycled roofing material,and more particularly, abrasive particles, within a roofing product.

Two types of coatings were prepared. The first type of coating includeda filled virgin asphalt mixture, wherein the filler was principallycalcium carbonate in the form of limestone. The first type of coatingdid not include any recycled roofing material. The second type ofcoating included a combination of a filled virgin asphalt mixture and 17weight % recycled roofing material. The first type of coating materialhad no or an insignificant amount of abrasive particles, and second typeof coating material included a significant amount of abrasive particles,mostly from roofing granules. Each of Control 1, Control 2, and Exampleincluded a fiberglass mat having substantially the same composition andstructure.

Control 1 included a roofing product in which the first type of coatingmaterial was used during two coating actions. The first action wasperformed to embed the first type of coating material within a perimetervolume defined by the fiberglass mat. The second action was performed tocoat the first type of coating material over the fiberglass mat afterthe fiberglass mat was embedded with the first type of coating material.Control 1 included no recycled roofing material.

Control 2 included a roofing product in which the second type of coatingmaterial was used during two coating actions. The first action wasperformed to embed the second type of coating material within aperimeter volume defined by the fiberglass mat. The second action wasperformed to coat the second type of coating material over thefiberglass mat after the fiberglass mat was embedded with the secondtype of coating material. Control 2 included recycled roofing material,including abrasive particles, within the perimeter volume of thefiberglass mat and within the separate coating.

The Example included a roofing product in which the first type ofcoating material was used during a first coating action, and the secondtype of coating material is used during a second coating action. Thefirst action was performed to embed the first type of coating materialwithin a perimeter volume defined by the fiberglass mat. Thus, norecycled roofing material was disposed within the perimeter volume, andtherefore, no or an insignificant amount of abrasive particles waswithin the perimeter volume. The second action was performed to coat thesecond type of coating material over the fiberglass mat after thefiberglass was embedded with the first type of coating material. Withinthe Example, the second coating includes recycled roofing material.Thus, the Example used recycled roofing material, wherein abrasiveparticles from the recycled roofing material did not contact or madeonly incidental contact with the outer most part of the fiberglass mat.

Controls 1 and 2 and the Example were tested after initially formed andafter aging. With respect to aging, Controls 1 and 2 and the Examplewere aged for 21 days in a dark oven at 158° F. (70° C.) per ASTMD5869-07a, section 4.4. Each of the roofing products was subjected to atear test. The particular tear test was performed as described in ASTMD-1922 as modified in D-228-08. Table 4 includes the data collected.

TABLE 4 Control 1 Control 2 Example Initial Tear Test (g) CrossDirection, av. 1152 965 1111 Cross Direction, std. 32 70 36 MachineDirection, av. 1236 955 1092 Machine Direction, std. 138 60 86 Aged TearTest (g) Cross Direction, av. 1232 907 1211 Cross Direction, std. 39 4882 Machine Direction, av. 1328 997 1120 Machine Direction, std. 166 87105

FIG. 8 includes a bar graph displaying the average tear strength for theroofing products, as initially manufactured, in the machine direction(MD, direction in which the roofing product is processed by themanufacturing equipment) and the cross direction (CD, directionperpendicular to MD). FIG. 9 includes a bar graph displaying the averagetear strength for the roofing products, after aging, in the machinedirection and the cross direction. Clearly, the Example has a highertear strength as compared to Control 2, both initially and after aging.For the initial tear test, the Example has a tear strength approximately15% and 14% greater as compared to Control 2 in the cross direction andmachine direction, respectively. For the aged test, the Example has atear strength of approximately 34% and 12% greater as compared toControl 2 in the cross direction and machine direction, respectively.

The Example has a tear strength closer to Control 1 than when Control 2is also compared to Control 1. In the cross direction, the Example hasalmost the same tear strength as Control 1. More specifically, in thecross direction, the Example has approximately 96% and 98% of the tearstrength of Control 1 for the initially manufactured and aged tests,respectively. Control 2 clearly has a lower tear strength, and typicallyis less than 80% of the tear strength of Control 1. In the crossdirection, Control 2 has approximately 84% and 74% of the tear strengthof Control 1 for the initially manufactured and aged tests,respectively. In the machine direction, the Example has approximately88% and 84% of the tear strength of Control 1 for the initiallymanufactured and aged tests, respectively. In the machine direction,Control 2 has approximately 75% and 74% of the tear strength of Control1 for the initially manufactured and aged tests, respectively.

A particular roofing product in accordance with an embodiment describedherein has superior tear strength characteristics as compared to otherroofing products that include recycled roofing material. As usedhereinafter, an embedded abrasives roofing product refers to a roofingproduct having substantially the same construction as the particularroofing product except that a significant amount of abrasive particlesare disposed within the perimeter volume of a ceramic base material, anda recycle-free roofing product refers to a roofing product havingsubstantially the same construction as the particular roofing productexcept that the roofing product includes substantially no recycledroofing material.

The tear strength for the particular roofing product is greater than theembedded abrasives roofing product. In a particular embodiment, theforce needed to tear the particular roofing product can be at leastapproximately 5% greater than the embedded abrasives roofing product. Inanother embodiment, the difference in force can be at leastapproximately 10% greater, in a further embodiment, the difference inforce can be at least approximately 15% greater.

When each of the particular roofing product and the embedded abrasivesroofing product is compared to the recycle-free roofing product, thetear strength for the particular roofing product can be closer to thetear strength of the recycle-free roofing product than when the embeddedabrasives roofing product is compared to the recycle-free roofingproduct. In the machine direction, the tear strength of the particularroofing product can be at least approximately 80% of the tear strengthof the recycle-free roofing product. Further, in the machine direction,the tear strength of the particular roofing product can be at leastapproximately 85% of the tear strength of the recycle-free roofingproduct. In the cross direction, the tear strength of the particularroofing product can be at least approximately 85% of the tear strengthof the recycle-free roofing product. Further, in the cross direction,the tear strength of the particular roofing product can be at leastapproximately 90% or even 95% of the tear strength of the recycle-freeroofing product.

Many different aspects and embodiments are possible. Some of thoseaspects and embodiments are described herein. After reading thisspecification, skilled artisans will appreciate that those aspects andembodiments are only illustrative and do not limit the scope of thepresent invention.

In a first aspect, a roofing product can include a ceramic base materialhaving an open structure. The roofing product can also include abituminous material substantially filling the open structure, whereinthe bituminous material has no greater than approximately 5 weight % ofabrasive particles. The roofing product can further include a recycledroofing material adjacent to the bituminous material.

In an embodiment of the first aspect, the roofing product furtherincludes a release sheet abutting the bituminous material. In anotherembodiment, the roofing product further includes a release sheetabutting the recycled roofing material and spaced apart from the ceramicbase material. In still another embodiment, the ceramic base materialincludes a vitreous ceramic composition. In a further embodiment, theceramic base material includes fiberglass. In still a furtherembodiment, the ceramic base material includes a non-vitreous ceramiccomposition.

In another embodiment of the first aspect, a volume occupied by thebituminous material is at least as large as a perimeter volume of theceramic base material. In another embodiment, a volume occupied by thebituminous material is less than approximately a perimeter volumeoccupied by the ceramic base material. In a particular embodiment, aportion of the recycled roofing material contacts a portion of theceramic base material. In a further embodiment, the bituminous materialincludes virgin asphalt. In still a further embodiment, the bituminousmaterial includes virgin asphalt and a plasticizer.

In another embodiment of the first aspect, the bituminous materialincludes no greater than approximately 80 weight % of filler. In stillanother embodiment, the bituminous material includes approximately 64weight % to approximately 70 weight % of filler. In yet anotherembodiment, the roofing product includes a membrane-type roofingproduct, and the bituminous material includes no greater thanapproximately 60 weight % of filler. In a further embodiment, thebituminous material includes filler particles, wherein a hardness of thefiller particles within the bituminous material is less thanapproximately a hardness of the ceramic base material. In still afurther embodiment, the filler particles within the bituminous materialinclude limestone.

In another embodiment of the first aspect, the recycled roofing materialincludes at least approximately 5 weight % recycled roofing articles. Instill another embodiment, the recycled roofing material includes atleast approximately 10 weight % recycled roofing articles. In yetanother embodiment, the recycled roofing material includes at leastapproximately 20 weight % recycled roofing articles. In a furtherembodiment, the recycled roofing material includes at leastapproximately 30 weight % recycled roofing articles. In still a furtherembodiment, the recycled roofing material includes at leastapproximately 35 weight % recycled roofing articles. In yet a furtherembodiment, the recycled roofing material includes at leastapproximately 39 weight % recycled roofing articles.

In another embodiment, of the first aspect, the recycled roofingmaterial includes abrasive particles. In a particular embodiment, theceramic base material has a ceramic base material hardness, the abrasiveparticles have a characteristic abrasive particle hardness, and theceramic base material hardness is less than the characteristic abrasiveparticle hardness. In a more particular embodiment, the abrasiveparticles include inert base particles. In another particularembodiment, the characteristic abrasive particle hardness corresponds tothe inert base particles. In still another particular embodiment, theabrasive particles further include a metal compound-containing coatingover the inert base particles. In an even more particular embodiment,the characteristic abrasive particle hardness corresponds to the metalcompound-containing coating. In a further particular embodiment, theroofing product further includes roofing granules along an exposedsurface of the roofing product and spaced apart from the ceramic basematerial. In more particular embodiment, the roofing granules have acharacteristic roofing granule hardness, and the ceramic base materialhardness is less than the characteristic roofing granule hardness.

In another embodiment of the first aspect, the roofing product is in aform of a roofing shingle. In still another embodiment, the roofingproduct is in a form of a roofing membrane. In yet another embodiment,the bituminous material has no greater than approximately 3 weight % ofabrasive particles. In a further embodiment, the bituminous material hasno greater than approximately 2 weight % of abrasive particles. In yet afurther embodiment, the bituminous material is substantially free ofabrasive particles.

In another embodiment of the first aspect, a characteristic particlesize of the recycled roofing material is smaller than a characteristicparticle size of the bituminous material. In still another embodiment, acharacteristic particle size of the recycled roofing material is nogreater than 70% of a characteristic particle size of the bituminousmaterial. In yet another embodiment, a characteristic particle size ofthe recycled roofing material is no greater than 50% of a characteristicparticle size of the bituminous material.

In a second aspect, a roofing product can include a ceramic basematerial occupying a perimeter volume, and a bituminous material withinthe perimeter volume, wherein the bituminous material does not includeany recycled roofing articles. The roofing product can include arecycled roofing material adjacent to the bituminous material. Theroofing product can have a characteristic selected from a groupconsisting of (1) the roofing product has a tear strength higher than atear strength of a first different roofing product having substantiallythe same structure, wherein the first different roofing product includesthe ceramic base material, and wherein abrasive particles are disposedwithin a perimeter volume of the ceramic base material; (2) in the crossdirection, the roofing product has a tear strength of at leastapproximately 85% of a tear strength of a second different roofingproduct having substantially the same composition, except the seconddifferent roofing product does not include any recycled roofingarticles; (3) in the machine direction, the roofing product has a tearstrength of at least approximately 80% of a tear strength of the seconddifferent roofing product; (4) a characteristic particle size of therecycled roofing material is smaller than a characteristic particle sizeof the bituminous material; (5) the roofing product includes a bimodalparticle size distribution; and (6) the recycled roofing material has ahigher metal content than the bituminous material.

In an embodiment of the second aspect, the roofing product has a tearstrength higher than a tear strength of the first different roofingproduct. In another embodiment, in the cross direction, the roofingproduct has a tear strength of at least approximately 85% of a tearstrength of the second different roofing product. In still anotherembodiment, in the cross direction, the roofing product has a tearstrength of at least approximately 90% of a tear strength of the seconddifferent roofing product. In yet another embodiment, in the crossdirection, the roofing product has a tear strength of at leastapproximately 95% of a tear strength of the second different roofingproduct. In a further embodiment, in the machine direction, the roofingproduct has a tear strength of at least approximately 85% of a tearstrength of the second different roofing product.

In another embodiment of the second aspect, the characteristic particlesize of the recycled roofing material is smaller than the characteristicparticle size of the bituminous material. In a particular embodiment,the characteristic particle size of the recycled roofing material is nomore than approximately 70% of the characteristic particle size of thebituminous material. In another particular embodiment, thecharacteristic particle size of the recycled roofing material is no morethan approximately 50% of the characteristic particle size of thebituminous material. In still another embodiment, the characteristicparticle size of the recycled roofing material is no more thanapproximately 30% of the characteristic particle size of the bituminousmaterial. In a further embodiment, the characteristic particle size ofthe recycled roofing material is a median particle size of particleswithin the recycled roofing material, and the characteristic particlesize of the bituminous material is a median particle size of particleswithin the bituminous material. In still a further embodiment, theroofing product includes a bimodal particle size distribution.

In another embodiment of the second aspect, the recycled roofingmaterial has a higher metal content than the bituminous material. In aparticular embodiment, the metal content for a particular materialincludes a mass of one or more metals in elemental or alloy form dividedby a total mass of a particular material times 100%. In still anotherparticular embodiment, the bituminous material has substantially zerometal content. In yet another embodiment, the recycled roofing materialhas a metal content of at least 0.1 weight %.

In a further embodiment of the second aspect, the ceramic base materialhas a ceramic base material hardness, the recycled roofing materialincludes abrasive particles having a characteristic abrasive particlehardness, and the ceramic base material hardness is less than thecharacteristic abrasive particle hardness. In a particular embodiment,the abrasive particles include inert base particles. In a moreparticular embodiment, the characteristic abrasive particle hardnesscorresponds to the inert base particles. In another more particularembodiment, the abrasive particles further include a metalcompound-containing coating over the inert base particles. In an evenmore particular embodiment, the characteristic abrasive particlehardness corresponds to the metal compound-containing coating. Inanother particular embodiment, the roofing product further includesroofing granules along an exposed surface of the roofing product andspaced apart from the ceramic base material. In a more particularembodiment, the roofing granules have a characteristic roofing granulehardness, and the ceramic base material hardness is less than thecharacteristic roofing granule hardness.

In another embodiment of the second aspect, the ceramic base materialincludes a vitreous ceramic composition. In still another embodiment,the ceramic base material includes fiberglass. In yet anotherembodiment, the ceramic base material includes a non-vitreous ceramiccomposition.

In an embodiment of the second aspect, the roofing product furtherincludes a bituminous material within an open structure of the ceramicbase material. In a particular embodiment, the bituminous material hasno greater than approximately 5 weight % of abrasive particles. Inanother particular embodiment, the bituminous material has no greaterthan approximately 3 weight % of abrasive particles. In still anotherparticular embodiment, the bituminous material has no greater thanapproximately 2 weight % of abrasive particles. In a further particularembodiment, the bituminous material is substantially free of abrasiveparticles.

In a further particular embodiment, a volume occupied by the bituminousmaterial is at least as large as a perimeter volume of the ceramic basematerial. In a more particular embodiment, a portion of the recycledroofing material is spaced apart from the ceramic base material. Inanother particular embodiment, a volume occupied by the bituminousmaterial is less than a perimeter volume occupied by the ceramic basematerial. In still another particular embodiment, the bituminousmaterial includes virgin asphalt. In yet another particular embodiment,the bituminous material includes virgin asphalt and a plasticizer. In afurther particular embodiment, the bituminous material includes asphaltand has no greater than approximately 80 weight % of filler. In still afurther particular embodiment, the bituminous material includesapproximately 64 weight % to approximately 70 weight % of filler. In yeta further particular embodiment, the roofing product includes amembrane-type roofing product, and the bituminous material includesbituminous and has no greater than approximately 60 weight % of filler.In another particular embodiment, the bituminous material includesfiller particles, wherein a hardness of the filler particles within thebituminous material is less than a hardness of the ceramic basematerial. In still another particular embodiment, the filler particleswithin the bituminous material include limestone.

In another embodiment of the second aspect, the recycled roofingmaterial includes at least approximately 5 weight % recycled roofingarticles. In another embodiment, the recycled roofing material includesat least approximately 10 weight % recycled roofing articles. In stillanother embodiment, the recycled roofing material includes at leastapproximately 20 weight % recycled roofing articles. In yet anotherembodiment, the recycled roofing material includes at leastapproximately 30 weight % recycled roofing articles. In a furtherembodiment, the recycled roofing material includes at leastapproximately 35 weight % recycled roofing articles. In still a furtherembodiment, the recycled roofing material includes at leastapproximately 39 weight % recycled roofing articles. In yet a furtherembodiment, the roofing product further includes a release sheetdisposed along an exposed surface of the roofing product. In anotherembodiment, the roofing product is in a form of a roofing shingle. Instill another embodiment, the roofing product is in a form of a roofingmembrane.

In a third aspect, a method of forming a roofing product can includeproviding a ceramic base material having an open structure. The methodcan also include filling the open structure of the ceramic base materialwith a bituminous material, wherein the bituminous material has nogreater than approximately 5 weight % of abrasive particles. The methodcan further include applying a recycled roofing material adjacent to theceramic base material after filling the open structure of the ceramicbase material with the bituminous material.

In an embodiment of the third aspect, filling the open structure of theceramic base material includes saturating the ceramic base material withthe bituminous material to substantially fill the open structure of theceramic base material.

In another embodiment of the third aspect, the method further includesheating the bituminous material such that it is in a softened state, andwherein filling the open structure of the ceramic base material includessubmerging ceramic base material into the softened bituminous material.In a particular embodiment, the method further includes increasing aviscosity of the softened bituminous material before applying therecycled roofing material. In another particular embodiment, heating thebituminous material includes heating virgin asphalt. In still anotherparticular embodiment, heating the bituminous material includes heatinga mixture of asphalt and filler. In a more particular embodiment, afiller content is less than 80 weight % of the mixture. In another moreparticular embodiment, a filler content includes approximately 64 weight% to approximately 70 weight % of the mixture. In still another moreparticular embodiment, the roofing product includes a membrane-typeroofing product, and a filler content is less than 60 weight % of themixture. In a further more particular embodiment, the bituminousmaterial includes filler particles having a hardness that is less than ahardness of the ceramic base material. In an even more particularembodiment, the filler particles within the bituminous material includelimestone. In still a further more particular embodiment, heating thebituminous material is performed such that the asphalt is in thesoftened state, and the filler remains in a solid state. In yet afurther more particular embodiment, heating the bituminous materialincludes heating a mixture of asphalt and a plasticizer. In an even moreparticular embodiment, heating the bituminous material is performed suchthat the asphalt and plasticizer are in the softened state.

In another embodiment of the third aspect, after filling the openstructure, the bituminous material occupies a volume no greater than aperimeter volume of the ceramic base material. In still anotherembodiment, after filling the open structure, the bituminous materialoccupies a volume greater than a perimeter volume of the ceramic basematerial.

In yet another embodiment of the third aspect, the method furtherincludes forming the recycled roofing material. In a particularembodiment, forming the recycled roofing material includes heating amixture of asphalt and recycled roofing articles. In a furtherembodiment, the recycled roofing articles include post-consumer roofingarticles. In still a further embodiment, the recycled roofing articlesinclude pre-consumer roofing articles. In yet a further embodiment, therecycled roofing articles include post-industrial roofing articles. In aparticular embodiment, the recycled roofing articles includepre-consumer roofing articles. In a more particular embodiment, therecycled roofing articles include post-consumer roofing articles. Inanother embodiment, the recycled roofing articles make up at leastapproximately 5 weight % of the recycled roofing material. In stillanother embodiment, the recycled roofing articles make up at leastapproximately 10 weight % of the recycled roofing material. In yetanother embodiment, the recycled roofing articles make up at leastapproximately 20 weight % of the recycled roofing material. In a furtherembodiment, the recycled roofing articles make up at least approximately30 weight % of the recycled roofing material. In still a furtherembodiment, the recycled roofing articles make up at least approximately35 weight % of the recycled roofing material. In yet a furtherembodiment, the recycled roofing articles make up at least approximately39 weight % of the recycled roofing material. In another embodiment, therecycled roofing material has a softening point no greater than 125° C.In still another embodiment, the recycled roofing material has asoftening point no greater than 105° C.

In a further embodiment of the third aspect, applying a recycled roofingmaterial is performed such that the recycled roofing material isadjacent to one of principal sides of the ceramic base material. Instill a further embodiment, applying the recycled roofing material isperformed such that the recycled roofing material is adjacent toopposite principal sides of the ceramic base material.

In another embodiment of the third aspect, the method further includesapplying roofing granules to an exposed surface of the roofing productafter applying the recycled roofing material. In still anotherembodiment, the method further includes applying a release sheet to anexposed surface of the roofing product after applying the recycledroofing material. In yet another embodiment, a characteristic particlesize of the recycled roofing material is smaller than a characteristicparticle size of the bituminous material. In a further embodiment, acharacteristic particle size of the recycled roofing material is nogreater than % of a characteristic particle size of the bituminousmaterial. In still a further embodiment, a characteristic particle sizeof the recycled roofing material is no greater than 50% of acharacteristic particle size of the bituminous material. In anotherembodiment, the method is performed such that the roofing product is ina form of a roofing shingle. In still another embodiment, the method isperformed such that the roofing product is in a form of a roofingmembrane.

Note that not all of the activities described above in the generaldescription or the examples are required, that a portion of a specificactivity may not be required, and that one or more further activitiesmay be performed in addition to those described. Still further, theorder in which activities are listed is not necessarily the order inwhich they are performed.

Certain features are, for clarity, described herein in the context ofseparate embodiments, may also be provided in combination in a singleembodiment. Conversely, various features that are, for brevity,described in the context of a single embodiment, may also be providedseparately or in any subcombination. Further, reference to values statedin ranges includes each and every value within that range.

Benefits, other advantages, and solutions to problems have beendescribed above with regard to specific embodiments. However, thebenefits, advantages, solutions to problems, and any feature(s) that maycause any benefit, advantage, or solution to occur or become morepronounced are not to be construed as a critical, required, or essentialfeature of any or all the claims.

It is to be appreciated that certain features are, for clarity,described herein in the context of separate embodiments, and may also beprovided in combination in a single embodiment. Conversely, variousfeatures that are, for brevity, described in the context of a singleembodiment, may also be provided separately or in any subcombination.Further, reference to values stated in ranges includes each and everyvalue within that range.

The specification and illustrations of the embodiments described hereinare intended to provide a general understanding of the structure of thevarious embodiments. The specification and illustrations are notintended to serve as an exhaustive and comprehensive description of allof the elements and features of apparatus and systems that use thestructures or methods described herein. Separate embodiments may also beprovided in combination in a single embodiment, and conversely, variousfeatures that are, for brevity, described in the context of a singleembodiment, may also be provided separately or in any subcombination.Further, reference to values stated in ranges includes each and everyvalue within that range. Many other embodiments may be apparent toskilled artisans only after reading this specification. Otherembodiments may be used and derived from the disclosure, such that astructural substitution, logical substitution, or another change may bemade without departing from the scope of the disclosure. Accordingly,the disclosure is to be regarded as illustrative rather thanrestrictive.

1. A method of forming a roofing product comprising: providing a ceramicbase material having an open structure; filling the open structure ofthe ceramic base material with a bituminous material, wherein thebituminous material has no greater than approximately 5 weight % ofabrasive particles; and applying a first layer of a first recycledroofing material along a first principal surface of the ceramic basematerial after filling the open structure of the ceramic base materialwith the bituminous material.
 2. The method of claim 1, furthercomprising applying a second layer of a second recycled roofing materialalong a first or second principal surface of the ceramic base materialafter filling the open structure of the ceramic base material with thebituminous material, wherein the second principal surface is oppositethe first principal surface.
 3. The method of claim 2, wherein the firstand second recycled materials are the same recycled material.
 4. Themethod of claim 3, wherein the first and second recycled materials aredifferent recycled materials.
 5. The method of claim 2, wherein applyingthe second layer of the second recycled material is applied along thefirst principal surface.
 6. The method of claim 2, wherein applying thesecond layer of the second recycled material is applied along the secondprincipal surface.
 7. The method of claim 1, wherein the bituminousmaterial has no greater than approximately 3 weight % of abrasiveparticles.
 8. The method of claim 1, further comprising heating thebituminous material such that it is in a softened state, wherein:heating the bituminous material comprises heating a mixture of asphaltand filler, and a filler content in the bituminous material is less than80 weight % of the mixture; and filling the open structure of theceramic base material comprises submerging ceramic base material intothe softened bituminous material.
 9. The method of claim 1, furthercomprising heating the bituminous material such that it is in a softenedstate, wherein: heating the bituminous material comprises heating amixture of asphalt and filler, and a filler content in the bituminousmaterial is less than 80 weight % of the mixture; and filling the openstructure of the ceramic base material comprises coating the bituminousmaterial onto the ceramic base material.
 10. The method of claim 1,further comprising heating the bituminous material such that it is in asoftened state, wherein: the roofing product comprises a membrane-typeroofing product; heating the bituminous material heating the bituminousmaterial comprises heating a mixture of asphalt and filler, wherein afiller content of the bituminous material is less than 60 weight % ofthe mixture; and filling the open structure of the ceramic base materialcomprises submerging ceramic base material into the softened bituminousmaterial.
 11. The method of claim 1, further comprising heating thebituminous material such that it is in a softened state, wherein: theroofing product comprises a membrane-type roofing product; heating thebituminous material heating the bituminous material comprises heating amixture of asphalt and filler, wherein a filler content of thebituminous material is less than 60 weight % of the mixture; and fillingthe open structure of the ceramic base material comprises coating thebituminous material onto the ceramic base material.
 12. The method ofclaim 1, wherein the recycled roofing material has a softening point nogreater than 105° C.
 13. The method of claim 1, wherein a characteristicparticle size of the recycled roofing material is no greater than 70% ofa characteristic particle size of the bituminous material.
 14. Themethod of claim 1, wherein the method is performed such that the roofingproduct is in a form of a roofing shingle.
 15. The method of claim 1,wherein the method is performed such that the roofing product is in aform of a roofing membrane.
 16. The method of claim 1, furthercomprising preparing the recycled roofing material using an attritor.17. The method of claim 16, wherein preparing the recycled roofingmaterial comprises: mixing a first portion of roofing articles withinthe attritor, wherein mixing is performed using an agitator; stoppingthe agitator after mixing the first portion of roofing articles; addinga second portion of roofing articles to the attritor after stopping theagitator.
 18. A method of forming a roofing product comprising:providing a ceramic base material having an open structure; filling theopen structure of the ceramic base material with a bituminous material,wherein the bituminous material has no greater than approximately 5weight % of abrasive particles; and applying a recycled roofing materialadjacent to the ceramic base material after filling the open structureof the ceramic base material with the bituminous material, wherein therecycled roofing material has at least 2 weight % acid-insoluble solids.19. The method of claim 18, wherein the acid-insoluble solids areHCl-insoluble solids.
 20. A method of forming a roofing productcomprising: providing a ceramic base material having an open structure;filling the open structure of the ceramic base material with abituminous material, wherein the bituminous material has a firstparticle size distribution; and applying a recycled roofing materialadjacent to the ceramic base material after filling the open structureof the ceramic base material with the bituminous material, wherein therecycled roofing material has a second particle size distribution thatis narrower than the first particle size distribution.
 21. The method ofclaim 20, wherein: the first particle size distribution has a firstmedian size greater than 40 microns; and the second particle sizedistribution has a second median size no greater than 40 microns. 22.The method of claim 20, wherein: the first particle size distributionhas a 95^(th) percentile size greater than 100 microns; and the secondparticle size distribution has a 95^(th) percentile size less than 100microns.